The present invention relates to the general field of aviation.
More particularly it relates to monitoring the oil consumption of an aeroengine in operation, such as a turbine engine, for example.
In order to estimate the oil consumption of an aeroengine, it is known to count the number of cans of oil poured into the tank of the engine during planned maintenance of the engine (e.g. between successive missions). The quantity of oil corresponding to the number of cans poured in on each filling is recorded on a sheet, and a sliding average is calculated over a plurality of fillings so as to obtain an estimate of the mean oil consumption of the engine. The estimate is then compared with a predetermined reference threshold in order to detect abnormal oil consumption by the engine.
That technique is implemented manually by most airlines. In addition, it does not take account of the difference between oil levels in the tank between the beginning and the end of the period over which the mean is calculated, and that can lead to inaccuracies in the estimated oil consumption.
A second technique that airlines use in certain maintenance computers consists in measuring the level of oil contained in the tank before each takeoff and after each landing of the aircraft. The oil levels as measured in that way are then compared in order to estimate oil consumption over the mission of the aircraft.
It can thus be understood that in order to obtain a reliable estimate of the oil consumption of the engine, that technique requires relatively accurate oil level sensors to be used. Furthermore, that technique does not take account of the quantity of oil that is circulating outside the tank, which quantity may vary depending on various parameters (oil viscosity, engine speed, etc.).